The work proposed for the 08 year of this research grant will continue to be approximately equally divided between clinico-pathologic studies of different human renal diseases and some experimental models. In man, work will continue with emphasis on long range followup of patients with lupus nephritis, and on the pleomorphic renal lesions associated with dysproteinemias. A new study of immunoperoxidase methods applied to renal biopsies is well underway. In the experimental animals, work will continue on the effects of diet-induced hyperlipemia in the aggravation of the renal lesions seen in aminonucleoside nephrosis and in spontaneous hypertensive rats. The role of hypercalcemia in the induction and/or aggravation of Bence Jones cast nephropathy in the mouse will continue and later extended to an evaluation of the role of hydropenia and acidosis in this disease process. Morphologically, both human and experimental studies are based on detailed light-, electron, and immunoflourescence- and immunoperoxidase-microscopic evaluation of single or sequential renal biopsies. Appropriate laboratory and functional methods will be correlated with the morphologic findings in an attempt to gain a better understanding of the functional and clinical significance of the different types of lesions detected in the kidneys.